Profile of patients with axial spondyloarthritis in Latin America: first report from the ESPALDA-PANLAR registry.

Despite increasing recognition of axial spondyloarthritis (axSpA) in Latin America, regional data remain scarce. This study aims to describe the clinical, laboratory, and imaging features of axSpA in Latin America using data from the ESPALDA-PANLAR registry. A cross-sectional analysis was conducted using baseline data from the ESPALDA registry, which includes patients with axSpA across seven Latin American countries. Demographic, clinical, laboratory, and imaging data were collected. Patients were stratified by sex, HLA-B27 status, and radiographic classification. Multivariable logistic regression was performed to identify independent associations. A total of 220 patients were included (56% male), with a mean age of 46 years and median diagnostic delay of 93 months (IQR: 13-122). HLA-B27 was positive in 60% of patients, and 62% met radiographic axSpA classification criteria. In multivariable analysis, radiographic axSpA was independently associated with male sex (OR 4.22; 95% CI 1.53-11.59), SI joint erosions on MRI (OR 3.98; 95% CI 1.45-10.90), and longer diagnostic delay (OR 1.01 per month; 95% CI 1.00-1.01). HLA-B27 positivity was associated with bone marrow edema on MRI (OR 2.81; 95% CI 1.50-5.26) and inversely with psoriasis (OR 0.14; 95% CI 0.06-0.33). This first report from the ESPALDA registry highlights distinctive features of axSpA in Latin America, including lower HLA-B27 prevalence and remarkably diagnostic delay. These findings underscore the need for earlier recognition and regionally adapted strategies for diagnosis and management.